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All Springer/NP/PCP Air Gun Discussion General => American/U.S. Air Gun Gates => Crosman-Benjamin Air Gun Gate => Topic started by: ivanpros on August 13, 2011, 11:58:13 PM

Title: Benjamin Trail NP will not zero after one month
Post by: ivanpros on August 13, 2011, 11:58:13 PM
Hi,
I bought the Benjamin Trail NP (.22) from Pyramid Air back in late June. I have been taking it out on the weekends to shoot. As of yesterday I went out to shoot and It is now shooting high (Crosman Premier Hollow Point). I adjusted the vertical adjustment down and it is at it's limit, but still shooting 2 mil dots too high ( just a note that I am very proficient with the scope adjustments and adjust them for my Gamos all the time).

I changed the scope to a Leapers to see if it was the scope, but it also shoots high with the vertical adjustment all the way down.

This looks like the opposite of barrel droop. Are there any known issued or does anyone have any other tips on what to check for?  :-\
Title: Re: Benjamin Trail NP will not zero after one month
Post by: Jman on August 14, 2011, 12:43:13 AM
did you accidently let the barrel slam shut before? Thats all I can think of. Shim the bottom of the front mount?
Title: Re: Benjamin Trail NP will not zero after one month
Post by: ivanpros on August 14, 2011, 12:50:05 AM
Nothing out of the ordinary when loading pellets. I just tried 2 shims (35 mm cut to size) and it is not enough. My grouping is still good when I shoot at 10 yds and 25 yds, other than just too high.
Title: Re: Benjamin Trail NP will not zero after one month
Post by: Jman on August 14, 2011, 01:02:14 AM
weird. You could contact crosman...thats about all else I can think of besides shims
Title: Re: Benjamin Trail NP will not zero after one month
Post by: ivanpros on August 14, 2011, 01:09:10 AM
I guess  I will try Ccrosman next. Can the shroud affect the barrel in any way or is it just aesthetic and sound dampening?
Title: Re: Benjamin Trail NP will not zero after one month
Post by: dkwflight on August 14, 2011, 01:17:59 AM
Hi
Shim the scope mount.
Title: Re: Benjamin Trail NP will not zero after one month
Post by: amb5500c on August 14, 2011, 01:18:56 AM
The shroud can affect the poi if something happened that causes it to clip the pellet as its leaving the barrel thereby deflecting the flight path.
Richard
Title: Re: Benjamin Trail NP will not zero after one month
Post by: Jman on August 14, 2011, 01:23:28 AM
As far as I know its only aesthetic and sound dampening! Cause the way it works is its just an empty pipe over the barrel that captures gas behind the pellet as it leaves the barrel
Title: Re: Benjamin Trail NP will not zero after one month
Post by: ivanpros on August 14, 2011, 01:33:54 AM
o.k. since I am getting tight shot groups I can make that a low priority for troubleshooting. I also tightened the barrel screw, for which I found was a little loose, and used goo gone on the barrel, but all that did was tighten my shot groups.
Title: Re: Benjamin Trail NP will not zero after one month
Post by: Wee Hooker on August 14, 2011, 02:11:24 AM
 Any chance your lifting your head as the shot goes off?
Title: Re: Benjamin Trail NP will not zero after one month
Post by: josh3rd on August 14, 2011, 03:59:19 AM
have someone else try to shoot and see if it may be your error or the rifle.  2nd, switch mounts.  the one thats in the front will be switched with the one in the rear.  3rd, over tightening of the barrel shroud can change poi.  try 1/16, 1/8 or 1/4 turns.
Title: Re: Benjamin Trail NP will not zero after one month
Post by: LeadHead on August 14, 2011, 09:57:51 AM
had that same prob with my NP All Weather. Swapped out my scope and got 2 slices of film for shimming. I figure it was the scope and seems there is some droop in their mounts too, according to my CMM at work, approximately 4=5 degrees
Title: Re: Benjamin Trail NP will not zero after one month
Post by: john on August 14, 2011, 01:45:06 PM
Got my Trail last March. If your groups are tight, you are very fortunate.

1. ANY change to the shroud will change poi. I have done ALOT of experimenting w/ my shroud.

2. The shroud is not easily removed due to factory glue (loktite knock off?) on muzzle threads. You would definitely NOT want to be trying to tighten that any further.

3. If you do remove the shroud, lay the gun over on its side, sight along the top edge of the compression tube and down the barrel. Presence or absence of droop is easy to see. In fact you can do that now.

4. Buris Signature scope rings for Weaver mounts plus a set of their plastic inserts will allow you hopefully to cancel out enough misalignment to get your elevation adjustment back to the middle of its range. I'm using them to cancel droop with no problems...well worth the $$$.

Keep us informed...oh, and welcome to GTA...i'm new too.
Title: Re: Benjamin Trail NP will not zero after one month
Post by: ivanpros on August 14, 2011, 07:34:17 PM
Well, I went ahead and removed the shroud of the barrel and I also found the factory glue and metal debri, which could be from the pellets or gunk left by manufacturer; It was dirty. Next I looked at the barrel and noticed that it was bent upward so I went ahead and bent it back down and it fixed the problem, but I am perplexed of how it happened. If it was dropped the shroud is so thin it would have showed damage and it would have taken a good bang to bend it. Well here are my  shot groups at 10 yards. I left the 2 shims in the fron scope mounts; since I did not want to bend the barrel too much.

(http://www.gatewaytoairguns.org/GTA/MGalleryItem.php?id=306)
Title: Re: Benjamin Trail NP will not zero after one month
Post by: Muppit on August 14, 2011, 07:41:44 PM
i have read dry firing a crosman/benjamin break barrel will bend the barrel upward. i had this problem with my g1 extreme as a beginner i would just push the pellet out and dry fire the rifle and i noticed that after a while i was always hitting a couple inches high read up on it someware and thats what was said caused it to bend upward........dave
Title: Re: Benjamin Trail NP will not zero after one month
Post by: john on August 14, 2011, 10:06:05 PM
So you've known all along how to fix droop and you just been sandbagging us.  ;D ;D
Title: Re: Benjamin Trail NP will not zero after one month
Post by: ivanpros on August 14, 2011, 11:59:03 PM
Actually no, everyone's comments got the mental wheels moving and common sense set in  :D . The answer may be right in front, but can't see it until someone else removes the mental obstacles out of the way. That was my first barrel bend and glad all went well.

Thanks to all!
Title: Re: Benjamin Trail NP will not zero after one month
Post by: john on August 15, 2011, 12:21:25 AM
No Ivan, I was kidding Muppit.  ;) Glad you fixed your problem. I learned something new.
Title: Re: Benjamin Trail NP will not zero after one month
Post by: ivanpros on August 15, 2011, 12:46:43 AM
Thanks John. Just a note that I test fired it without the shroud after every attempt at bending it and it was just enough to feel the barrel flex slightly. When I screwed the shroud back on it did slightly change my point of zero, but was very small and I was able to adjust back to zero.
Title: Re: Benjamin Trail NP will not zero after one month
Post by: ezman604 on August 15, 2011, 09:42:51 AM
Excellent, glad you were successful in straightening the barrel. Overtightening the shroud end can buckle a barrel slightly. Airgunning is fun and you learn a lot if you stick with it. One point I want to make, dry firing does not cause a bent barrel. And it's not just Crosman /Benjamin break barrels either, but ANY springer/NP gun can be damaged by dry firing. Dry firing is cocking the gun and shooting it without a pellet loaded. This can cause main seal damage and possibly damage a spring.
What causes a barrel to get bent is a different beast. What happens here is you are cocking the gun and before you can engage the sear to cock the gun, the barrel slips from your hand and slams shut. It can also happen if you cock the gun and let go of the barrel while getting and loading a pellet. If the anti-beartrap or sear fail, or you inadvertently hit the trigger while the barrel is in the break position, it will slam shut. This will most definitely cause the barrel to get bent, most likely crack a stock, possibly cut a finger tip off or worse. ALWAYS hold the barrel until you have completely loaded it and locked it into the firing position!!!!
Keep us informed on your progress.
Happy Shooting!!!!
Dave
 8)
Title: Re: Benjamin Trail NP will not zero after one month
Post by: PyroMonkey on August 17, 2011, 11:48:07 AM
I know it's unrelated but when you had the shroud off was the gun louder?  I know suppressors don't do much on spring piston guns but did you notice any difference?
Title: Re: Benjamin Trail NP will not zero after one month
Post by: EJB on August 17, 2011, 12:42:30 PM
Can the barrel be straightened if this happens?  It would be nice to know if it happens.
Title: Re: Benjamin Trail NP will not zero after one month
Post by: ivanpros on August 18, 2011, 12:11:46 AM
I could not tell much difference with the shroud off. It was a little longer burst, but not louder. It has been 3 days and it works fine since I bent it.
Title: Re: Benjamin Trail NP will not zero after one month
Post by: BIMsparky on August 18, 2011, 07:40:20 PM
Ivanpros,

I just joined! Glad you found the problem and were able to bend it back to straight... What pellets are you using and what is your NP's caliber? I've had the .177 Trail NP for about 1 month- I like it alot, but it can be hold sensitive, and only after about 600 rds did it finally start to group for me, which could have just been me learning to shoot the thing. Those are good groups considering the rifle (I think anyway)! I have finally gotten several 3 shot groups with touching holes, but if I try for a 5 shot group, I am usually dissapointed...

Have the straightshooters .177 sampler pack arriving today, can't wait to see how different pellets do...

Happy shooting-
Title: Re: Benjamin Trail NP will not zero after one month
Post by: ivanpros on August 18, 2011, 10:19:36 PM
BIMSparky,

Glad to see you joined. The people on these forums are very helpful on here and there is much to be learned by everyone. I have the .22 and I have noticed it is not as hold sensitive as any of my Gamo springers. I am still experimenting with different brands myself. Here is my best to worst so far.

Crosman Premier Pointed (tightest shot groups, but I am hoping the brown box domes will be even better)
Crosman Premier Hollow Point (decent groups)
Gamo Hunter (large skirts stick out and are not flush when loaded; large groups)
Predator Polymags (very nice fit, but very large groups)

tested at 10 yards, 15 yards, 25 yards. When I get a chance I will post some numbers and charts.

Welcome aboard.
Title: Re: Benjamin Trail NP will not zero after one month
Post by: BIMsparky on August 19, 2011, 03:31:23 AM
Thanks Ivanpros!

Wow, I'm glad I didn't start off with a Gamo then- I was just about pullin my hair out for a while. Thanks for the info on those different pellets- I will have to try some of those CPP's to see if she likes them or not.

I got my sampler and shot groups with about 8 different pellets- I'll post some pics soon, but the difference blew me away! I had one group with HN Baracuda Powers that was one elongated hole at 20 yds- I am very happy with that after the results I had been getting.

I am looking forward to learning from all you guys, this seems like a great group of alot of experienced, friendly and helpful people!

Cheers-

Title: Re: Benjamin Trail NP will not zero after one month
Post by: BIMsparky on August 19, 2011, 03:33:08 AM
Hey by the way, how do you like your GRT-III? I still have the stock trigger and am wondering if you notice an improvement in accuracy...
Title: Re: Benjamin Trail NP will not zero after one month
Post by: ivanpros on August 19, 2011, 11:16:57 AM
Yes, huge difference. That long creeping trigger was reduced to a nice hair trigger. Over-adjusting the screw I noticed it will not cock properly; need to make fine adjustments for final preference.
Title: Re: Benjamin Trail NP will not zero after one month
Post by: Deane on August 19, 2011, 11:46:18 AM
After firing about 1,000 through my Gamo .177 Whisper and about 400 rounds through my Benji .22 Titan, the triggers worked in quite nicely. Of course that's with the understanding that most of my experience is with military and they are so stiff you could hang from them. I'd probably kill myself with a hair trigger ;D That said, I do have a GRT IV to install on my Whisper and will get one for my Titan.
Title: Re: Benjamin Trail NP will not zero after one month
Post by: BIMsparky on August 19, 2011, 12:26:36 PM
Great- I definitely need to get one of those- I think it will help with the hold too...
Title: Re: Benjamin Trail NP will not zero after one month
Post by: john on August 19, 2011, 11:16:24 PM
Closest mine's ever gotten to zero today...10 pellets in one ragged 3/4" hole...but can he do it again...?...and I was aiming at that intersection, not the center dot  ;D
Title: Re: Benjamin Trail NP will not zero after one month
Post by: Deane on August 20, 2011, 11:30:29 AM
How many rounds through it since you had it tuned? With about 250 rounds through it, my .22 Benji Titan (same as the Trail without the extras) gave me a three-string, 10-shot per string average of 718.4 and standard deviations of 3.74, 5.2, and 3.16. I'm using 14.3 gn CPHPs for my break-in.

Sorry, I didn't see your signature. My bad.
Title: Re: Benjamin Trail NP will not zero after one month
Post by: john on August 20, 2011, 02:17:12 PM
How many rounds through it since you had it tuned?
Actually the vast majority of those rounds in my signature were before tuning. Only about 300rounds thru it since. Never had group that tight before. I really did not expect tuning to improve accuracy, velocity yes…accuracy?, pleasant surprise IF it lasts.

Edit: fyi, no, it didn't last.
Title: Re: Benjamin Trail NP will not zero after one month
Post by: The Shootist on April 23, 2013, 11:33:05 PM
Good information! I have been reading and lurking this forum for several months I did a search tonight and came across this thread. I recently purchased a brand new Trail NP from Pyramid Air that is shooting 12" high and 5" to the right and that was right out of the box. I ran out of adjustment on Two Scopes I have tried and even changed rings and couldn't get it on the mark. Dooshed the barrel cleaned real good and have shot over 250 rounds through the rifle. Best I could get it in was 6" high and 2" to the right. After reading this thread I removed the barrel shroud and put a straight edge on the barrel and it was 3/8" bent high and 1/8" to the right. I straightened the barrel and got it within .0005 according to my trusty feeler gauges.  ;)  I am looking fwd to testing it out tomorrow after work. Thanks &  Great Forum.
~Duke
Title: Re: Benjamin Trail NP will not zero after one month
Post by: Tater on April 24, 2013, 12:47:18 AM
Good information! I have been reading and lurking this forum for several months I did a search tonight and came across this thread. I recently purchased a brand new Trail NP from Pyramid Air that is shooting 12" high and 5" to the right and that was right out of the box. I ran out of adjustment on Two Scopes I have tried and even changed rings and couldn't get it on the mark. Dooshed the barrel cleaned real good and have shot over 250 rounds through the rifle. Best I could get it in was 6" high and 2" to the right. After reading this thread I removed the barrel shroud and put a straight edge on the barrel and it was 3/8" bent high and 1/8" to the right. I straightened the barrel and got it within .0005 according to my trusty feeler gauges.  ;)  I am looking fwd to testing it out tomorrow after work. Thanks &  Great Forum.
~Duke


Good luck. I hope it's all "straightened out" now.   ;)
Title: Re: Benjamin Trail NP will not zero after one month
Post by: john on April 24, 2013, 01:34:18 AM
@The Shootist

Welcome to GTA and thanks for posting. Us Trail NP owners have to stick together! 8) I also have straightened two Trail NP barrel/breechblock assemblies enough to get them to where the scope could be dialed in and still remain near the mechanical centers of both windage and elevation. Didn't shrink the groups though. :'(
Please keep us informed...anyone who discovers & shares how to make this gun behave could make alot of people happy.
Title: Re: Benjamin Trail NP will not zero after one month
Post by: GutPile on April 24, 2013, 02:41:50 AM
I've had the Benji Trail NP for about a week now.  I started with that same ragged 10-shot 10-yard 3/4" hole but I has gotten progressively worse (about 500 shots), and I'm lucky to get a 3" group now.  Talk about  >:(    I've made sure all my screws were tightened, scope was solid, etc, could not figure it out...

I've decided I am going to send it back to the hole it came from and order a Flying Dragon.  It's too bad, I was really excited about this rifle  :'(
Title: Re: Benjamin Trail NP will not zero after one month
Post by: john on April 24, 2013, 09:34:55 PM
@GutPile
Which Flying Dragon do you like?
Title: Re: Benjamin Trail NP will not zero after one month
Post by: GutPile on April 28, 2013, 02:31:11 AM
@GutPile
Which Flying Dragon do you like?

I think the XS25 with the full tune is a pretty safe bet, but I really have my eye on the XS46U in .22 with the gas ram configuration (and full tune).  The only problem, it's out of stock until who knows when...  >:(

I'm waiting for Mike to return from some gun convention he's at this week so I can get his opinion on these models.